As is known, a closing system for a door of a motor vehicle comprises a lock mounted on the door and a lock striker mounted in a fixed portion of the bodywork in the proximity of the opening of the door itself (or, more rarely, vice versa).
The lock basically comprises a closing mechanism designed to couple, in a releasable way, with the lock striker so as to obtain a relative blocking between the lock and the lock striker itself when the door is closed, and a lever-type actuating assembly, which can be connected to the manual-control elements associated to the door, such as, for instance, the internal and external handles, and which is designed to interact with the closing mechanism to control opening thereof.
The closing mechanism and the actuating assembly are normally mounted on a supporting assembly, which is, in turn, designed for being rigidly fixed to the corresponding door of the motor vehicle.
In particular, the supporting assembly defines a U-shaped seat for receiving the lock striker so as to enable its coupling to the closing mechanism and is formed by a metal frame and a shell made of plastic material, which are coupled together.
Supporting assemblies for locks of motor vehicles are known, in which the metal frame is made up of a pair of plates, which are fixed, on opposite sides, on the shell made of plastic material and which delimit with the latter a housing compartment for the closing mechanism. One of the plates is fixed, for example by means of screws, to the door, and, together with the other plate, supports a plurality of transverse pins for hinging the levers that form the closing mechanism and the actuating assembly. More precisely, the aforesaid pins are normally riveted, at their opposite ends, to the plates of the metal frame.
The supporting assemblies described above, albeit proving functionally valid, require the management of a relatively large number of components, which must be made to converge onto one and the same assembly line for being assembled together with one another and with the various levers of the closing mechanism and of the actuating assembly.
Furthermore, the greater the number of components that are to be assembled, the longer the overall duration of the assembly operations and the greater the deviation between the design dimensional values of the assembly to be made and the effective dimensional values of the assembly obtained, the said effective dimensional values suffering from inevitable play due to assembly between the components themselves.